Does conventional Oil cool engines better than Synthetic?

This started at a Harley dealer. I was there to talk to the person who runs the riders education there, I wanted a class for my son so he could get his license. I talked to some sales men and heard this gem from one of them, "A race mechanic told me that conventional oil actually cools an engine better than synthetic. The synthetic oil runs cooler because it does not take as much heat away from the engine as conventional oil. The oil is cooler, but the engine itself is hotter because it doesn't pull the heat from the parts. Of course this is only true for air cooled engines."
Needless to say I was stunned. Could someone really believe this?
Anyway, since I have an air cooled bike I decided to put this to a real test. Now this is not as purely scientific as I would like it to be, but it's the best I could do at the time.
I had originally planned to run both sets of numbers on the same day, but rain on the day I was going to do that prevented that. So instead this happened on consecutive days on my way home from work.

What I did was ride the same route each day home, 12 miles of freeway followed by 9 miles of stop and go traffic. This would have the bike fully up to operating temperature. Then I rode 3.5 miles at 60 MPH with no stops to get a nice even temperature, I then pulled into a parking spot and took temperature readings as quickly as I could.
Then I rode another 2 mile stretch and pulled over, but this time I allowed the bike to idle for 2 minutes before taking my readings to simulate temperatures while sitting at a stop light,
Finally I finished my ride home, stop and go traffic. This is the least controlled part of the ride. But I took temperature reads at home anyway just to ensure the temps had gone down from the stop light simulation.
All temperature readings were taken with the bike shut down to help stabilize the readings. I think any wind blowing would change the temperatures less than if I had left the bike running.

The Testing
The test Mule. My BMW R 1100 S.
OK, Testing starts with the Oil. I used Motorcycle Specific mineral oil. I didn't want the results affected by an oil that was not specific to motorcycles since my regular oil is motorcycle specific. This is the oil they had at my local bike shop, I expect other MC specific oils would have performed the same.
I used this infrared thermometer to take the temperature readings. Not lab quality but it will read consistently with itself so the results will still show if there is any difference between the temperatures the bike runs because of the different oil
I took temperature readings at several spots. First was in the center of the head. This is the top of the combustion chamber.
I also took readings at the exhaust port and on the barrel where the piston is moving through the bore I took these readings from both cylinders. I also took a reading of the oil sump, that would give me the temperature of the oil.

OK, here are the temperature readings from the first run with the mineral oil. On this run winds were light and it was partly cloudy. The stretch of road where I was able to hold my constant speed and take my temperature readings was in the shade of clouds most of the time.

Temperatures with the Mineral Oil
Temperature at the start of the ride	88 degrees
Winds at the start of the ride	Light
First set of readings, 3.5 miles at 60 MPH
Right Head	288.5 Degrees
Right Exhaust	279 Degrees
Right Barrel	270 Degrees
Left Head	279.5 Degrees
Left Exhaust	276.3 Degrees
Left Barrel	273 Degrees
Oil Sump	203 Degrees
Second set of readings, 2 miles at 60 MPH then 2 minute idle.
Right Head	300 Degrees
Right Exhaust	326 Degrees
Right Barrel	292 Degrees
Left Head	301 Degrees
Left Exhaust	301 Degrees
Left Barrel	284 Degrees
Oil Sump	222.8 Degrees
Third set of readings, Stop and go to home.
Right Head	302 Degrees
Right Exhaust	302 Degrees
Right Barrel	294 Degrees
Left Head	290 Degrees
Left Exhaust	296 Degrees
Left Barrel	284 Degrees
Oil Sump	215 Degrees

Not much change in temperature of the metal from the stop to my house, but the temperature of the oil in the sump did come down. So maybe a little more riding would have seen the metal temperatures coming down too.
Now it's time to change the oil and get my second set of readings

Now on to my normal oil. What can I say, I'm an Amsoil salesman. Although I'm sure other synthetic oils would work similarly.

On the next day, I took the exact same route and ran the same speeds, took the same rest at 2 minutes. The only thing I couldn't control was the traffic to my house after the stop light simulation. It was a little warmer, but not bad. Still Partly cloudy, and the 3.5 miles to the first readings was in the shade of clouds like the previous day.

Results

Overall the temperatures are a little higher with the synthetic oil but both metal temperatures and the oil temperature. I think this can be due to the higher outside temperature.
I believe the differences are statistically insignificant. Also The oil was not cooler as the, I'll call it an "Urban Legand" stated. So I see no elevated temperatures in the metal that can be attributed to the fact that the synthetis oil did not take away the heat. It is also clear that the synthetic oil is hotter, again counter to the "Urban Legand".
So I believe, as stated before, the differences can be simply attributed to the higher ambient temperature.

The other point here, for this "Urban Legand" to be true. The "Specific heat" of the oils would have to be different. In a basic description specific heat is a measure of a substances (Liquid, solid, gas) ability to absorb heat. This article in Wikipedia discusses the topic
So again, the oils would have to be a very different make up for the conventional oil to carry away more heat than the synthetic. And that is not the case.

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